Pyroelectric automatic door control circuit

This is the schematic diagram of the automatic door control circuit . Human body
movement detection uses the new pyroelectric infrared detection module
HN911. VT is used as delay control, and
the delay control pseudo time can be changed by adjusting the potentiometer RP. Optocoupler
MX:3020 plays the role of AC and DC isolation. When no one is walking
. HN911 output terminal ① is low power early. VT has no control
signal output, the triac VS is closed, the load motor
does not work, and the door is closed. When someone approaches the automatic
door. The HN911 module detects the infrared
energy radiated by the human body, the output terminal ① is high level , the bidirectional gate tube VT2 is turned on, the load motor works, and the automatic door is opened. When the automatic door is in place,
the limit switch S cuts off the power supply. Since the output level of the HN911 module output terminal ② is exactly opposite to the level
of the output terminal ①, the output of the output terminal ② can be used to control the closing of the automatic door .